This study is intended to elaborate and extend the literature on Dehydroepiandrosterone (DHEA) effects on cognitive functioning, activities of daily living (ADL), and quality of life (QOL) as part of the first clinical trial of DHEA on Senile Dementia of the Alzheimer's type (SDAT). It is suggested that an intervention that ameliorated or slowed the effects of the dementia would have a very significant impact on the high human, social and economic costs of caring for SDAT patients, as well as beneficially affecting general quality of life for older adults. The literature suggests that DHEA has significant correlations with cognitive, QOL and ADL improvements in elderly and demented adults, but such effects have only been measured using very global, non-differentiated measures. The present proposal is an in- depth analysis of changes in functioning across more domains (cognition, ADL, QOL, biochemical) with a finer degree of analysis than has been carried out to date, using six-month data gathered as part of the clinical trial on 30 SDAT patients receiving DHEA and 30 placebo control SDAT patients. The functional domains (cognitive, QOL, ADL) are each assessed by a set of variables from psychometric and functional tests and batteries chosen due to sensitivity to SDAT and/or previously reported changes due to DHEA. Sets of functional variables will be analyzed by repeated measures multivariate ANOVA; univariate tests will identify variables for a correlational analysis with DHEA/cortisol changes. Alpha level protection and corrections for non-parametric data will be used. It is hypothesized that within each of the domains the combined set of predictor variables will show significant improvement in the DHEA group; further, individual variables that differ significantly between placebo and control groups will correlate significantly with changes in DHEA/cortisol levels.